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Sometimes you use a library that has a bug. Or maybe it doesn’t has a bug but you want to change something. Of course if it is an open source you can get the sources… build them … with your change and so on. However this first takes a lot of time and second you need the sources.
What you usually want .. is to just replace one class.. or few classes with something custom… maybe add a line .. or remove a line and so on.
Yesterday… I had an issue with jboss-logging. The version I was using was 3.2.0Beta1 and it turns out that using this version and log4j2 2.0 final basically meant that no log is send to log4j2. The reason was a null pointer exception that was catched in jboss logging class called Log4j2Logger. The bug I submitted is here https://issues.jboss.org/browse/JBLOGGING-107 and it was fixed at the same day. However I will use it as an example since I didn’t knew when this will be fixed.. and I didn’t want to wait till it is fixed.
So I was thinking what I want.. to take the jbo…

When you use Hibernate and DAO pattern it is a good idea to use a Generic Base Dao. The fallowing code snippet contains GenericDAO that is a base class for all my DAO classes. This GenericDAO uses HibernateDaoSupport from Spring for its implementation if you want you can use JpaDaoSupport or JdbcDaoSupport in your projects. My Generic DAO interface looks like this :package org.joke.myproject.dao.base;import java.io.Serializable;import java.util.List;/*** @authorNaidenGochev* @param<E>* @param<PK>*/publicinterface GenericDao<E,PK extends Serializable> { PK save(E newInstance);void update(E transientObject);void saveOrUpdate(E transientObject);void delete(E persistentObject); E findById(PK id); List<E> findAll(); List<E> findAllByProperty(String propertyName,Object value);}All method names are very common so I don't think they need some explanation.The implementation of this GenericDAO :package org.joke.myproject.dao.base;import java.io.Ser…

It is little strange that no one really uses emptyList like he should in Java. So this is small post showing how to use the emptyList method in the Collections class. Question: How to create an empty list ? lets assume that we have a class Book with multiple titles. So the class in our examples will be:import java.util.List;publicclass Book {private List<String> titles;publicvoid setTitles(List<String> titles) {this.titles = titles; }public List<String> getTitles() {returntitles; }}Lets say that in our snippet we have something like : Book myCrazyBook=new Book(); and we want to assign an empty list to the titles in this book. This is a common scenario if you want to set something to be emptyList in specific case instead of null. So of course your first try will be something like: Answer 1: myCrazyBook.setTitles(new ArrayList()); -WARRNING - ArrayList is a raw type. References to generic type ArrayList<E> should be parameterized Ok…